Glycine-Assisted Fabrication of N-Doped Graphene-Supported Uniform Multipetal PtAg Nanoflowers for Enhanced Ethanol and Ethylene Glycol Oxidation

The pursuit of efficient electrocatalysts with better activity, stability, and controllable morphology and size for alcohol oxidation is of decisive significance yet challenging for the application of direct alcohol fuel cells (DAFCs) in large scale. Herein, a series of glycine-assisted N-doped graphene (NG)-supported multipetal PtAg nanoflowers (NFs) has been successfully engineered to serve as high-performance electrocatalysts for ethanol electrooxidation and ethylene glycol electrooxidation catalysis. The introduction of glycine and NG played important roles on the size evolution, where the size decreased by around 7 nm, and well dispersion of PtAg NFs, respectively, which assisted in the formation of PtAg nanoparticles with high surface areas and optimized multipetal structure. The multipetal PtAg NFs exhibit great improvement in electrochemical activity and durability toward the ethanol oxidation reaction (EOR) and ethylene glycol oxidation reaction (EGOR), whose mass activities are 3598.4 and 4587.2 mA mg(-1), respectively. Meanwhile, with the promoting impact of glycine and NG, the as-obtained PtAg NFs can even retain 49.8% and 41.2% of the initial catalytic activity for EOR and EGOR after 500 cycles. This work suggests that PtAg NFs with superior electrochemical activity and stability are one of the optimized choices for high-performance catalysts toward alcohol oxidation.